Terrestria

Terrestria is the plane on which the planet Earth is located.

EDIT: Due to limited Magic information, the best assumption is that planes are individual planets. No other information can be garnered from the true Magic: the Gathering storyline. The best explanation for our universe being in the MtG multiverse is billions of overlays on a gigantic plane, causing each individual cosmic body that exists in real life.

EDIT: The formation of a seperate article, i.e. 'The AoM Multiverse' is suggested.

It is commonly accepted that a plane is not a planet, though in most cases the focus of a plane will take place on a particular planet within this plane. The confusion arises in that most planes are confused with planets, due to the fact that most planes are named after their primary planets.([1]). Each plane is a seperate 'universe' however, the word itself has the stigmatic effect of only meaning there can be one 'verse'. Each 'verse' is a plane, within a wider multiverse. This given it means that any number, and any variant of a plane is possible within the multiverse, it can be said that the Magic multiverse contains an infinite number of planes. ([2]). As part of the possibility, and as is used in these storylines, Terrestria is part of this multiverse.